Positioning controls for splicing rollstands



June 20, 1967 W. F. HUCK POSITIONING CONTROLS FOR SPLICING ROLLSTANDS 5 Sheets-Sheet 1 Filed July 9, 1965 mm mm INVENTOR. WILLIAM F. HUCK ATTORNEY June 20, 1967 w, 3,326,485

POSITIONING CONTROLS FOR SPLICING ROLLSTANDS Filed July 9, 1965 5 Sheets-Sheet 2 INVENTOR.

WILLIAM F. HUCK ATTORNEY W. F. HUCK POSITIONING CONTROLS FOR SPLICING ROLLSTANDS June 20, 1967 5 Sheets-Sheet Filed July 9, 1965 INVENTOR. WILLIAM F. HUCK AT ORNEY June 20, 1967 w, p HUCK POSITIONING CONTROLS FOR SPLICING ROLLSTANDS 5 Sheets$heet 4 Filed July 9, 1965 m GI United States Patent 3,326,485 PGSETHONING CONTRGLS FOR SPLICING ROLLSTANDS William F. Huck, S1 Greenway Terrace, Forest Hills, N.Y. 11375 Filed July 9, 1965, Ser. No. 470,672 18 Claims. (Cl. 242-583) This invention relates generally to rollstands in which a web being delivered or unwound from a web supply roll about to expire is spliced to the leading end of the web forming a new web supply roll so that web material can be continuously delivered from one web supply roll after another, for example, to a printing press or other web processing machine.

In splicing rollstands of the type to which this invention relates, support means are provided for carrying a first web roll from which a web is being unwound and a second or new web roll which is to have its leading end, at the roll periphery, spliced to the web from the first roll, and the support means are displaceable to move the new web roll to splicing position adjacent a run of the web from the first roll which is guided to extend across the path of movement of the second or new roll to splicing position.

During movement of the new web roll to splicing position, a splicing assembly which includes a paster pressure brush or rollers is moved toward the run of the web from the first or expiring roll so as to be operable thereon from the side of the run facing away from the new roll at splicing position. At the splicing position, the new web roll is rotated about its own axis so as to more or less match its peripheral speed to the speed of movement of the adjacent run of the web being unwound from the expiring web roll. When the rotated new web roll is in the angular or rotational position about its axis at which adhesive previously applied to the periphery of the roll, preferably near the leading end of its web, faces toward the adjacent run of the web from the expiring roll, the splicing assembly is actuated to cause the paster brush or rollers to press the web run against the adhesive and thereby join or splice the web of the new roll to the web from the expiring roll, whereupon cutters sever the web from the expiring roll at a location between the latter and the splice.

In order to achieve satisfactory splicing in a rollstand of the above type, it is necessary that there be a predetermined distance between the periphery of the new roll at splicing position and the web run from the expiring roll, and also that the splicing assembly be at a predetermined position relative to that web run when it is actuated. If too small a distance exists between the periphery of the new roll at splicing position and the web run from the expiring roll, premature pasting may occur, that is, the expiring web run may contact the periphery of the new roll before actuation of the splicing assembly and thus have inadequate adherence to the adhesive. If there is too large a distance between the periphery of the new roll at splicing position and the expiring web run, excessive tension is produced in the web run by the impact of the paster pressure brush or rollers thereagainst in defiecting the web run across that large distance into contact with the periphery of the new roll. Such excessive tension may cause the web to break or may prevent adequate adherence of the expiring web run to the adhesive on the new roll periphery. If the splicing assembly is positioned too close to the expiring web run premature pasting may again result. If the splicing assembly is positioned at too large a distance from the expiring web run, the paster pressure brush or rollers and the cutters, in the case where the latter are part of the splicing assembly, may not be capable of reaching and acting on the expiring web run when the splicing assembly is actuated.

3,325,485 Patented June 20, 1957 ice When the successive rolls from which a web is to be delivered continuously are all of the same diameter, the displacement of the support means for moving a new web roll to splicing position and the movement of the splicing assembly toward the expiring web run may be stopped at predetermined fixed locations so as to always achieve the necessary distances between the periphery of the new roll at splicing position and the expiring web run and between the splicing assembly and the expiring web run. However, splicing rollstands are frequently required to handle web supply rolls having substantially different diameters, for example, in the range from 35 to 50 inches. It will be apparent that halting displacement of the roll carrying support means at a fixed location, that is, with each new roll having its axis at a fixed location when in splicing position, results in a distance between the new r-oll periphery and the expiring Web run that is far greater for a new roll of 35 inch diameter than for a new roll of 50 inch diameter.

In an attempt to ensure that each new web roll, when in splicing position, will have its periphery at a predetermined location relative to the expiring web run, irrespective of the diameter of the new web roll, it has been proposed, for example, in US. Patent No. 2,621,865, issued Dec. 16, 1952, to William C. Wieking, to limit displacement of the support means for moving the new roll to splicing position by sensing means which detects or responds to the arrival of the periphery of the new roll at a fixed location. Thus, each new web roll, irrespective of its diameter, has its periphery disposed at such fixed location when in splicing position. The disposition of the peripheryof each new roll at a fixed location, when in splicing position, could achieve the desired predetermined positioning of the new roll periphery relative to the expiring web run only if the path of the expiring web run, and hence its position relative to the new roll periphery at the fixed location, did not change for new web rolls of different diameters.

However, in splicing rollstands of the described type, the roll carrying support means, which may be in the form of spider arms rotatable about an axis located between the rolls carried thereby, transports each roll in a closed path so that displacement of the support means to move a new web roll toward splicing position simultaneously moves the expiring roll in an opposite direction and thereby displaces the expiring web run toward the new web roll. Since the extent of displacement of the support means required to dispose the periphery of the new web roll at a fixed location is inversely proportional to the diameter of the new web roll, the dis lacement of the expiring web run toward the new web roll will be similarly inversely proportional to the diameter of the new roll. Thus, the expiring web run will be closer to the periphery of a relatively small diameter new web roll than to the periphery of a relatively large diameter new web roll, even though the peripheries of both rolls are at the same fixed location when in splicing position. Further, by reason of the displacement of the expiring web run toward the new web roll moving to splicing position, positioning of the splicing assembly at a fixed location preparatory to its actuation causes the distance between the splicing assembly and expiring web run to be larger when the new web roll is of relatively small diameter than when the new roll is of relatively large diameter.

Although the aforesaid effects of displacement of the expiring web run during movement of a new web roll to splicing position may be somewhat reduced by providing a spider assembly or reel carrying more than two equally angularly spaced rolls, or by providing guide rollers between the web rollers on the spider assembly, such measures complicate the structure of the spider assembly and do not sufficiently avoid the mentioned problems when used with web rolls having a wide range of diameters.

Accordingly, it is an object of this invention to provide a splicing rollstand for delivering a web continuously from one web supply roll after another and having means for achieving accurately uniform locating of the periphery of each new web roll relative to the expiring web run, when at splicing position, irrespective of the diameter of the new r-oll.

Another object is to provide a splicing rollstand of the described character also having means for achieving accurately uniform locating of the splicing assembly relative to the expiring web run when each new web roll is at splicing position, and irrespective of the diameter of the new roll.

In accordance with an aspect of this invention, a splicing rollstand of the described character is provided with sensing means to detect the approach of the periphery of each new web roll to splicing position, and the position of such sensing means is changed in accordance with the displacement of the expiring web run toward the new web roll as the latter moves toward splicing position, whereby the sensing means detects the periphery of the new web roll at a predetermined location thereof realtive to the expiring web run irrespective of the diameter of the new web roll.

In the case where a drive means is energized to displace the roll-carrying support means for moving a new Web supply roll to splicing position, such drive means may be deenergized in response to the detection of the periphery of the new web roll by the sensing means to halt displacement of the support means when the periphery of the new roll is at the desired location relative to the expiring webrun irresmctive of the diameter of the new roll.

In a referred embodiment of the invention, the sensing means is carried by movable mounting means having follower means engaging a cam displaceable with the roll-carrying support means so that changing 'of the position of the sensing means is determined by such cam in response to displacement thereof with the support means.

Further, it is a feature of this invention, to limit the movement of the splicing assembly toward the expiring web run by means of a movable stop, and to change the position of the movable stop in accordance with the displacement of the expiring web run as the new web roll and such run approach each other, for example, by connecting the stop for movement with the movable mounting means for the sensing means.

It is another feature of this invention to effect operation of the splicing assembly in response to the detection, by the sensing means, of a predetermined angular position of the new web roll about its axis when such roll is at splicing position. In one embodiment of this feature, the sensing means is positioned to detect the periphery of the new roll when the same is at a predetermined distance from the expiring web run and a time delay is provided between such detection of the periphery of the new roll and deenergization of the drive means for displacing the roll-carrying support means. During the time delay, the drive means causes the new roll and the expiring web run to further approach each other and thereby dispose the new roll at splicing position, while the sensing means is then positioned to detect the predetermined angular position of the new roll at splicing position. In another embodiment, the sensing means includes two photocells movable together in accordance with displacement of the expiring web run and being positioned relative to each other to respectively detect the periphery of the new roll and its predetermined angular position when the new roll is at splicing position.

The above, and other objects, features and advantages of the invention, will be apparent in the following detailed description of illustrative embodiments thereof which is to be read in connection with the accompanying drawings wherein:

FIG. 1 is a schematic side elevational view of an automatic splicing rollstand embodying this invention, and being shown with a portion thereof partly broken away and in section;

FIG. 2 is an end elevational view shown partly in section along the line 22 on FIG. 1;

FIG. 3 is an enlarged, detail sectional view taken along the line 33 on FIG. 2;

FIG. 4 is a sectional view similar to that of FIG. 3, but taken along the line 4-4 on FIG. 2;

FIG. 5 is a schematic diagram of the electrical controls included in the illustrated rollstand;

FIG. 6 is a fragmentary viewrsimilar to a portion of FIG. 2, but showing a modified sensing device in accordance with the invention; and

FIG. 7 is .a schematic diagram showing the electrical controls to be used with the modified sensing device of FIG. 6.

Referring to the drawings in detail, it will be seen that considerable simplification has been effected in the several views of the drawings in order not to obscure the novel features characteristic of the invention with details of conventional parts well known to those skilled in the art. Also, where possible, conventional symbols have been used to represent known components.

The illustrated splicing rollstand embodying this invention is generally identified by the reference numeral 10 and is shown to include vertical side frame members A and B carrying bearings 11 (FIG. 2) in which the opposite end portions of a rotatable horizontal shaft or spindle 12 are journaled. The successive web supply =rolls from which web material is to be continuously delivered are rotatably supported between ends of a pair of spider arms 13a and 13b (FIG. 2) which are mounted, at their centers,

on spindle 12. Spindle 12 is rota-table by a gear 14 secured on an end of the spindle extending beyond side frame member A and meshing with a pinion 15 mounted on the shaft extension of a motor 16 carried by a bracket 17 secured to side frame member A.

During normal running of rollstand 10, spider arms 13a and 13b are disposed in the position shown in broken lines on FIG. 1 and the web W is unwound from a web supply roll Ia positioned at a normal running position R by the related ends of the spider arms. The web W unwound from web supply roll Ia passes upwardly around a roller 18 journaled in side frame members A and B and then travels to the right, as viewed on FIG. 1, so as to pass over a floating roller 19 which forms part of a variable speed drive mechanism 21) acting as a web tension control device.

Mechanism 20 includes a pair of arms 21 extending from a shaft 22 journaled in side frame members A and B and having roller 19 rotatably supported between their free ends. Roller 19 is urged upwardly into contact with web W, for example, by springs or fluid pressure operated cylinders (not shown) acting on arms 21. A cross shaft 23 journaled in side frame members A and B is suitably driven from the printing press or other web processing machine (not shown) to which the rollstand continuously delivers web material. An end of cross shaft 23 projecting beyond side frame member A carries a V-belt pulley 24 which engages and drives a V-belt 25 running around a variable diameter pulley 26. Variable diameter pulley 26 may be of the type disclosed in US. Patent No. 2,812,666, issued Nov. 12, 1957, to William F. Huck, and is secured on an end of a pulley shaft 27 which is journaled in side frame members A and B. The two runs of V-belt 25 between pulleys 24 and 26 pass under take-up pulleys 28 and 29. Pulley 28 is rotatably carried by an arm 30 secured to shaft 22, and pulley 29 is rotatably carried by an arm 31 which is pivotally mounted on a stub shaft 32 extending from the adjacent side frame member A. Arms 30 and 31 are connected by a turnbuckle link 33 which is adjustable to vary its effective length so that pulleys 28 and 29 can be thereby displaced toward and away from each other for initially adjusting the drive ratio between shafts 23 and 27 of tension control mechanism 20.

Shaft 27 has at least one drive pulley 34 secured thereon, and each drive pulley 34 is in driving engagement with a main unwinding or drive belt 35. The main unwinding or drive belt 35 travels downwardly towards the right, as viewed on FIG. 1, from its drive pulley 34 and passes successively around idler pulleys 36 and 37, a take-up pulley 38, and idler pulleys 39 and 40. The last mentioned idler pulley 40 is disposed below drive pulley 34 so that a run of drive belt 35 moving upwardly from idler pulley 40 to drive pulley 34, and being indicated in two different positions at Wr and Wr is frictionally engageable with the periphery of a web roll Ia when the roll is in the normal running position R, and also when spider arms 13a and 1317 are turned so as to dispose roll la in the expiring position E indicated in full lines on FIG. 1. The several idler pulleys 36, 37, 39 and 40 are rotatable on shafts suitably journaled in bearings carried at fixed locations by side frame members A and B. Take-up pulley 38 is rotatable on a shaft having its ends journaled in bearing blocks which are vertically movable in suitable guides (not shown) carried by the side frame members, and such bearing blocks are urged upwardly, as by springs or fluid pressure operated cylinders (not shown), so that take-up pulley 38 is urged upwardly to maintain a desired tension in drive belt 35 as the length of the belt included in the run engaging roll la is varied by reduction of the diameter of the roll and by movement thereof with the spider arms.

Web tension control device is generally similar to that disclosed in US. Patent No. 3,103,320, and operates in substantially the same way so as to maintain a substantially constant tension in the web being unwound from web roll la. The force exerted by springs or by fluid pressure operated cylinders to urge floating roller 19 upwardly and the similarly directed force exerted by belt on pulleys 28 and 29 are balanced, when the web tension is at a desired value, by the downward force exerted on floating roller 19 by the run of the web extending downwardly from the floating roller to an idler roller 41 positioned therebelow. An increase in the tension of web W above the desired value, moves roller 19 downwardly and causes clockwise turning of shaft 22 so that pulleys 28 and 29 are moved downwardly against the runs of belt 25. The resulting reduction in the effective length of belt 25 reduces the effective engagement diameter of belt 25 on variable speed pulley 26. Since belt 25 is traveling at a constant linear speed in proportion to the speed at which the web is propelled by the printing press or other web processing machine, such reduction in the effective diameter of pulley 26 increases its rotational speed and hence increases the speed of movement of main unwinding or drive belt 35 and of the web being unwound from web roll Ia. The feeding of web W at a faster rate effectively reduces the tension of the web acting on roller 19 and thereby restores the desired web tension.

Conversely, when the tension in web W decreases below the desired value, floating roller 19 is moved upwardly to effect similar upward movement of pulleys 28 and 29 and thereby increase the effective length of belt 25 and the effective engagement diameter of that belt on pulley 26. Thus, the rotational speed of pulley 26 is reduced to decrease the speed of movement of main unwinding or drive belt 35 and of the web being unwound from web roll Ia. The reduction in speed of the web increases the web tension acting on roller 19 so as to restore the desired value of web tension.

When a web roll Ia held between ends of spider arms 13a and 13b is disposed at the normal running position R and the web is being unwound therefrom, as described above, the opposite ends of the spider arms are disposed at a loading position L so as to receive a new web roll. After a substantial proportion of the web on roll Ia at the normal running position R has been unwound therefrom, motor 16 is energized, as hereinafter described, to effect rotation of spider arms 13a and 13b in the clockwise direction, as viewed on FIG. 1. Such angular or rotational displacement of spider arms 13a and 13b moves the new web supply roll toward splicing position S and simultaneously moves the expiring web roll Ia toward expiring position E. It will be apparent that the run of web W being unwound from roll Ia and which is guided by idler roller 18 extends across the path of travel of the new web roll moving toward splicing position S. Thus, as the new web roll moves toward splicing position, the periphery of that roll approaches the run of web W extended from expiring web roll In.

The illustrated rollstand 10 has an accelerating device 42 that includes at least one accelerating belt 43 which engages and is driven by a drive pulley 44 on a shaft 45 journaled in side frame members A and B. Shaft 45 is driven from shaft 27 by a belt and pulley transmission 46 so that, when accelerating device 42 is moved downwardly from the raised or inoperative position shown on FIG. 1, the run of belt 43 extending between drive pulley 44 and an idler pulley 46 carried by the ends of rockable arms 47 will engage the periphery of the new web roll at splicing position S and accelerate the new web roll up to a peripheral speed that matches the speed of movement of the adjacent run of web W being unwound from expiring roll Ia by main drive belt 35.

Upon movement of a new web roll to splicing position S, a splicing assembly 48 (FIGS. 2, 3 and 4) is moved toward the run of web W extending from expiring roll Ia so as to be operable on such run from the side thereof facing away from the new web roll at splicing position. When the peripheral speed of the new web roll at splicing position S substantially matches the speed of movement of web W being unwound from expiring roll Ia and the new web roll is in a predetermined angular or rotational position about its axis, splicing assembly 48 is actuated, as hereinafter described, to press the expiring web run against adhesive on the periphery of the new web roll and thereby join or splice the web of the new roll to the web from expiring roll Ia. Immediately after such splicing of the new roll to the expiring web run, splicing assembly 48 further acts to sever the expiring web run in back of the splice, that is, at a location between the splice and expiring roll Ia.

In order to achieve satisfactory splicing in the manner described above, it is necessary that the periphery of the new web roll, when in splicing position, be at a predetermined location relative to the expiring web run, and further that splicing assembly 48 be at a predetermined location relative to the expiring web run when the splicing assembly is actuated. If the successive web rolls from which a web is to be delivered continuously are all of the same initial diameter, each displacement of spider arms 13a and 13b for moving a new web roll to splicing position and each movement of splicing assembly 48 toward the expiring web run may be stopped at predetermined fixed locations so as to always achieve the necessary predetermined locations of the periphery of the new roll at splicing position and of the splicing assembly with respect to the expiring web run, for example, as disclosed in U.S. Patent No. 3,103,320, which is identified fully above.

However, splicing rollstands of the described character are frequently required to handle web supply rolls having substantially different initial diameters, for example, in the range from 35 to 50 inches. It will be apparent that stopping angular displacement of spider arms 13:: and 13b at a fixed location, that is, with each new web roll having its axis at a fixed location when in splicing position, would result in a distance between the new roll periphery and the expiring web run that is far greater for a new roll of 35 inch diameter than for a new roll the expiring web roll In in the opposite direction, that is,

downwardly and toward the left to expiring position B. By reason of such movement of expiring web roll Ia, the expiring Web run is displaced toward the left, as viewed on FIG. 1, that is, toward the new web roll approaching splicing position. The extent to which the expiring web run is displaced toward the new web roll approaching splicing position S depends upon the extent of angular displacement of spider arms 13a and 13b. Thus, if the angular displacement of the spider arms for moving a new web roll to splicing position is limited or controlled so as to dispose the periphery of the new roll at a fixed location irrespective of the roll diameter, the distance between the periphery of a relatively small diameter new web roll and the expiring web run will be less than the distance between the periphery of a relatively large diameter new web roll and the'expiring web run. Further, by reason of the above described displacement of the expiring Web run during movement of a new web roll toward splicing position, positioning of splicing assembly 48 at a fixed location preparatory to its actuation would result in a greater distance between the thus located splicing assembly and the expiring web run, in the case of a new web roll of relatively small diameter than in the case of a new web roll of relatively large diameter.

In accordance with the present invention, rollstand 10 variably limits angular displacement of spider arms 13a and 13b for moving a new web roll to splicing position so that the periphery of the new web roll, when in splicing position, is at a predetermined location relative to the expiring web run irrespective of the diameter of the new web roll. For example, as shown on FIG. 1, if the new web roll is of maximum diameter, for example, a diameter. of 50 inches; as represented at lb angular displacement of the spider arms is halted when the center lines thereof are at the position P to dispose the periphery of new roll Ib at a predetermined distance from the expiring web run which is then in the position indicated at Wr On the other hand, when the new web roll is of minimum diameter, as indicated at 112 angular displacement of the spider arms continues until the center lines thereof are at the position P so as to dispose the periphery of roll Ib at the same predetermined distance from the expiring web run which is then at the position indicated at Wr In the case of new web rolls having diameters intermediate the maximum and minimum diameters, as indicated at I12 and Ib angular displacement of the spider arms is halted at corresponding positions intermediate the posit-ions indicated at P and P so that for each new web roll at splicing position S, the periphery of the roll will be at the same uniform distance from the expiring web run disposed at a corresponding position between the expiring web run positions indicated at Wr and Wr In order to make possible the uniform or predetermined location of the periphery of each new web roll at splicing position with respect to the expiring web run, the approach of the periphery of the new web roll at splicing position is detected by a sensing device 49 which is moved in accordance with the displacement of the expiring web run as the new web roll and the expiring web run approach each other, whereby the sensing device 49 detects the new web roll at a predetermined location thereof relative to the expiring web run irrespective of the diameter of the new web roll.

In the illustrated rollstand 10, displacement of spider arms 13a and 13b for moving a new web roll to splicing position is automatically initiated by energizing the motor 16 when the web roll Ia at normal running position R has had its diameter reduced to a predetermined extent, and motor 16 is automatically deenergized, in response to the detection by sens-ing device 49 of the periphery of the new web roll approaching splicing position, whereby to halt arms 13a and 13b with the new web roll at a predetermined position relative to the expiring web run.

A suitable arrangement for controlling the operation of motor 16 in the manner indicated above may include a photoelectric sensing device 50, shown schematically in broken lines on :FIG. 1 and on FIG. 5, which is fixedly mounted to direct a light beam '51downwardly toward a fixedly mounted reflector 52. The light beam 51 is initially intercepted by the web roll Ia at normal running position I R. However, when the progressively decreasing diameter of roll Ia at position R has been reduced to the predetermined size shown on FIG. 1, light beam 51 passes the periphery of roll Iaand is reflected from reflector 52 so as to impinge on a photocell in sensing device 50.

As shown diagrammatically on FIG. 5, the photoelectric sensing device 50 is connected to a control panel 53 by way of leads 54, and control panel 53 is operative to close or permit current flow through a circuit therein between leads 55 and 56 when the photocell of sensing device 50v receives light reflected from reflector 52. Lead 55 is connected to a current supply line L and the other or grounded current supply line L is connected by a grounded lead 57 to a relay 58 which is, in turn, connected to a lead 59. Lead 59 extends to one side of a normally closed contact 60a of a time delay relay 60, and lead 56 extending from control panel 53 is connected to the'other side of normally closed contact 60a.

Thus, when control panel53 closes the circuit between leads '55 and 56, relay 58 is energized through closed contact 60a of relay 60. Energizing of relay 58 closes the normally open contact 58a thereof. A lead 61 extends from line L to one side of contact 58a, and a lead 62 extends from the other side of contact 58a to one side of 21 normally closed contact 60c of relay 60. A lead 63 extends from the other side of contact 600 to a motor starter 64 which is connected to motor 16 by way of conductors 65. The energizing circuit for motor starter 64 is completed by a grounded lead 66. Accordingly, energizing of relay 58 closes the circuit for energizing motor 16 through the contact 58a of relay 58 and the contact 600 of relay 60, and motor 16 is thereby operated to cause displacement of arms 13a and 13b for moving a new web roll toward splicing position.

The previously mentioned sensing device 49 for detecting the approach of the periphery of the new web roll to splicing position is also of the photoelectric type and is mounted, as hereinafter described in detail, at one side of the path traveled by the web rolls upon displacement of spider arms 13:: and 13b. Sensing device 49 is connected by leads 67 with'a control panel 68 from which a lead 69 extends to lead 62. Another lead 70 extends from controlpanel 68 to one side of a normally closed contact 6% of relay 60, and the other side of contact 60b is connected by a lead 71, the coil of a relay 72 and a lead 73 to ground.

The coil of time delay relay 60 is connected by a lead 74 to ground, and by a lead 75, the normally open contact 72a of relay 72 and a lead 76 to supply line L The sensing device 49 includes a light source directing a light beam 77 (FIG. 2) laterally therefrom toward a reflector 73 positioned at the opposite side of the path traveled by a new web roll in moving toward splicing position, and a photocell for receiving light reflected from reflector 78. So long as light beam 77 is not intercepted by a new web roll moving toward splicing position, control panel 68 responds to the reception of light by the photocell of sensing device 49 to open or block an in-' ternal circuit between leads 69 and 70. However, when light beam 77 is intercepted by the periphery of a new web roll approaching splicing position, the internal circuit of panel 68 is closed between leads 69 and 70, thereby to complete the circuit for energizing relay 72 through lead 73 and through lead 61, contact 58a of energized relay '58, leads 62, 69 and 70, closed contact 60b of deenergized relay 60 and lead 71. Energizing of relay 72 closes its contact 72a to energize time delay relay 60 by way of lead 74, and lead 75, contact 72a and lead 76. After expiration of a predetermined time delay, which may be adjusted, energized relay 60 is actuated or tripped to open its normally closed contacts 60a, 60b and 600 with the following results:

The opening of contact 60a interrupts the circuit for energizing relay 58 so that its contact 58a is opened and interrupts the energization of control panel 68 by way of lead 69 for rendering sensing device 49 inoperative.

The opening of contact 60b causes deenergization of relay 72 to open its contact 72a and thereby break the circuit for energization of relay 60 by way of leads 75 and 76.

The opening of contact 60c breaks the connection to motor starter 64 so that motor 16 is thereby deenergized to halt spider arms 13a and 13b at the moment when relay 60 is tripped or actuated.

In order to move sensing device 49 in accordance with the displacement of the expiring web run as the new web roll and the expiring web run approach each other during displacement of arms 13a and 13b, r-ollstand has sensing device 49 mounted on a bracket 79 (FIGS. 1 and 2) which extends from one end of a shaft 80 turnable in a suitable bearing 81 (FIG. 2) carried by side frame member A. Thus, sensing device 49 is movable in an arcuate path centered at the axis of shaft 80 and which is approximately parallel to the path of movement of the new web roll approaching splicing position.

Bracket 79 has an arm 82 (FIG. 1) extending therefrom and connected, at its end, to a tension spring 83 which is attached to the adjacent side frame member A, as at 84, whereby bracket 79 is urged in the counterclockwise direction, as viewed on FIG. 1. A stop pin 85 extends from side frame member A below arm 82 to limit turning of bracket 79 under the urging of spring 83. Bracket 79 further carries a cam follower roller 86 engageable with a cam 87 which may be an integral part of gear 14, as shown, or otherwise formed and mounted for displacement with arms 13a and 13b.

Cam 87 has two diametrically opposed contoured portions 88a and 88b positioned relative to arms 13a and 13b so that one of the other of these contoured portions engages cam follower roller 86 in the course of movement of a new web roll toward splicing position. As shown particularly with respect to portion 88a of the cam, each of contoured cam portions 88a and 88b includes a section 88' of progressively decreasing distance from the turning axis of cam 87 and a following section 88" of progressively increasing distance from such turning axis.

Shortly after angular displacement of arms 13a and 13b is commenced for moving a new web roll from loading position L to splicing position 3, section 88' of a contoured cam portion comes into engagement with cam follower roller 86 and thereby rocks bracket 79 in the clockwise direction, as viewed on FIG. 1, against the force of spring 83. Such clockwise rocking of bracket 79 moves sensing device 49 toward the right, that is, toward the expiriug web run, and thereby sets the sensing device beyond the position that would correspond to the location of the periphery of the largest web roll to be handled by the rollstand when such web roll is in the predetermined splicing position relative to the expiring web run. As the new web roll moves closer to splicing position, section 38 of the contoured cam portion engages roller 86 so as to permit progressive rocking of bracket 79 in the counterclockwise direction, by spring 83, so long as displacement of arms 13a and 13b is continued. Such counterclockwise rocking of bracket 79 moves sensing device 49 toward the left, as viewed on FIG. 1, that is, toward the periphery of the new web roll approaching splicing position or in the same general direction as the displacement of the expiring web run.

In accordance with this invention, the cam section 88" is shaped so that the movement of sensing device 49 resulting from engagement of cam section 88 with roller 86 corresponds to the similarly directed displacement of the expiring web run. Thus, irrespective of the diameter of the new web roll, sensing device 49 detects the periphery of the new web roll approaching splicing position when that periphery is at a predetermined location relative to the expiring web run.

Since time delay relay 60 is tripped to deenergize motor 16 at a predetermined or adjustably fixed time after sensing device 49 detects the approach of a new web roll to splicing position, it is apparent that each new Web roll, irrespective of its diameter, will move a predetermined distance beyond the position at Which its periphery is detected by sensing device 49 and come to rest at a splicing position where its periphery is at a predetermined location relative to the expiring web run.

During the further movement of the new web roll to splicing position following the detection of its periphery by sensing device 49, bracket 79 supporting the sensing device also undergoes further rocking movement in the counterclockwise direction, as viewed on FIG. 1, by reason of the further displacement of cam 87 with arms 13a and 13b. Thus, when the new web roll comes to rest at the predetermined splicing position relative to the expiring web run, sensing device 49 is positioned to direct its light beam against an end surface of the new web roll at a location spaced radially inward from the periphery of the roll by a predetermined distance for a purpose that will hereinafter be made apparent.

The splicing assembly may have brushes for pressing the expiring web run against adhesive on the peripheral surface of the new web roll, or that function may be performed by rollers, as in the splicing assembly 48 shown on FIGS. 2, 3 and 4.

The illustrated splicing assembly 48 includes a pair of support arms 89 secured to a shaft 90 which is journaled in side frame members A and B. Arms 89 depend from shaft 90 and are laterally located at opposite sides of main drive belt 35 so that the lower end portions 91 of the arms, which may be forked, as shown, can swing toward and away from the expiring web run in response to turning of shaft 90.

Forked lower end portion 91 of each arm 89 carries a lateral shaft 92. A bell-crank or bent lever 93 is rocka'bly mounted on shaft 92 between the sides of forked end portion 91 and includes an upwardly directed arm 93a and a rearwardiy directed arm 93b. Laterally extending shafts 94 are freely rotatable in bearings 95 (FIG. 4) carried by arms 93a of bell-cranks 93. Secured on each shaft 94 is a roller 96 extending inwardly from the related arm 89 and an end roller 97 projecting laterally outward from arm 89 so as to be engageable'with the expiring Web run at opposite sides of the main drive belt 35 when splice assembly 48 is actuated, as hereinafter described, to displace rollers 96 and 97 to the position indicated at 96 on FIG. 4 and thereby press the expiring web run Wr against the adjacent periphery of a new web roll Ib at splicing position.

Prior to actuation of splice assembly 48, each bellcrank 93 is held in the position shown on FIG. 4 by a latch 98 pivoted on a pin 99 extending through forked end portion 91 and engagea-ble with a latch pin 100 (shown in broken lines on FIG. 4) extending from arm 93]) of the bell-crank. A spring 101 is connected between latch 98 and an anchor 102 secured to forked end portion 91 to urge the latch into engagement with latch pin 100. A cable 103 extends from latch 98 so that an upward pull 1 1 on cable 103 rocks latch 98 in opposition to spring 101 and thereby releases latch pin 100. Release of latch- 98 from pin 100 frees bell-crank 93 for rocking in the counterclockwise direction, as viewed on FIG. 4, by a tension spring 104 extending between a pin 105 on arm 93b and a pin 106 carried by support arm 89.

The ends of each shaft 92 pivotally support a depending bracket 107 carrying a knife 108. Each bracket 107 has an arm 109 (FIG. 3) directed rearwardly therefrom and carrying a latch pin 110 which is engageable by a latch 111. Latch 1-11 is pivotally supported on the lower end portion 91 of arm 89, as at'112, and isurged into engagement with latch pin 110 by means of a spring 113.

A cable 114 extends upwardly from latch 111 so that an upward pull exerted on cable 114 releases latch 111 from pin 110 to permit rocking of bracket 107 in the clockwise direction, as viewed on FIGS. 3 and 4, thereby to move knife 108 from the retracted position shown in full lines on FIG. 4 to its operative or web-cutting position indicated in broken lines at 108'. The movement of bracket 107 for projecting knife 108 to its operative or cutting position is effected by a compression spring 115 (FIG. 3) which bears, at its opposite ends, against bracket 107 and against an end of pin 99, and which extends around a screw 116. One end of screw 1-16 is pivotally connected to bracket 107, as at 117, and the opposite end portion of screw 116 extends slidably through a diametric bore in pin 99 and carries adjustable stop nuts 118 for limiting the movement of knife or blade 108 to its web-cutting position and thereby preventing contact of the knife with the new web roll.

Each cable 103 (FIG. 4) is connected, at its upper end; to an arm 119 extending from a shaft 120 which extends laterally between, and is journaled in the upper portions of arms 89. Similarly, each cable 114 (FIG. 3)

is connected, at its upper end,*to an arm 121 extending from a shaft 122 which extends laterally between, and is journaled in support arms 89 below shaft 120. Arms 123 and 124 extend from shafts 120 and 122, respectively, and are pivotally connected to piston rods 125 and 126 extending from cylinders 127 and 128 mounted side-byside on a bracket 129 secured to one of support arms 89. Flexible conduits or hoses 130 and 131 extend to cylinders 127 and 128, respectively, for supplying fluid under pressure thereto.

It will be apparent that each latch 98 is released to permit rollers 96 and 97 to act or press against the expiring web run when fluid under pressure is supplied to cylinders 127, and that each latch 111 is released to permit knives 108 to cut the expiring web run when fluid under pressure is supplied to cylinder 128.

As shown particularly on FIGS. 1 and 2, splicing assembly 48 further includes an actuating arm 132 extending from shaft 90 substantially parallel to support arms 89 and being located adjacent side frame member A. The lower end portion of arm 132 is pivotally connected to a piston rod 133 extending from a double-acting, fluidpressure operated cylinder 134 which is pivotally supported by frame member A, as at 135. Flexible conduits or hoses 136 and -137 extend to the opposite ends of cylinder 134 for alternately supplying fluid under pressure thereto.

It will be apparent that, when fluid under pressure is supplied to cylinder "134 through conduit 136, piston rod 133 is retracted to swing splicing assembly 48 rearwardly or away from the web run traveling upwardly to idler roller 18. During such rearward swinging of splicing assembly 48, fixed cams (not shown) carried by the rollstand frame engage a cam follower roller or pin 138 FIG. 4) extending from each bell-crank 93 for returning the latter to its latched position. Similarly, during rearward swinging of splicing assembly 48, fixed cams (not shown) engage a cam follower roller or pin 139 (FIG. 3) carried by an arm 140 which is angularly fixed relative to each knife carrying bracket 107 so' as to return the latter to its latched position.

When fluid under pressure is admitted to cylinder 134 by way of conduit 137, piston rod 133 is extended and thereby moves splice assembly 48 toward the expiring web run.

As shown schematically on FIG. 5, a solenoid controlled valve 138 may be provided to control the supplying of fluid under pressure to cylinder 134. When valve 138 is deenergized, fluid is supplied by way of conduit 136 to return splicing assembly to its inoperative position. When valve 138 is energized, fluid is supplied to cylinder 134 by way of conduit 137, thereby to move splicing assembly toward a position where its rollers 96 and 97 and knives 108 are operable on the expiring web run. The circuit for energizing solenoid valve 138 may include a selfhold relay 139 connected to control panel 53 by a lead and to ground by a lead 141. Relay 139 is initially energized by current received from panel 53 when sensing device 50 detects the reduction of the diameter of the web roll In at the running position R to a predetermined dimension. Such energization of relay 139 closes its normally open contact 139a which is interposed between a lead 142 extending from line L and a lead 143 extending to solenoid valve 138, thereby to energize valve 138 and cause movement of splicing assembly 48 toward the expiring web run.

After initial energization of relay 139 by control panel 53, the energization of relay 139 may be maintained through a hold circuit 144 so that the tripping of relay 60 when the new web roll reaches the splicing position, as described above, will not affect the energization of solenoid valve 138.

In accordance with the present invention, as previously mentioned herein, the movement of splicing assembly 48 toward the expiring web run in response to energization of valve 138 is limited or stopped at a predetermined location relative to the expiring web run irrespective of the diameter of the new web roll moving to splicing position, and hence also irrespective of the extent of the displacement of the expiring web run occurring as a result of the movement of the expiring web roll in the opposite direction to that of the movement of the new web roll. Thus,

when the new web roll is in its splicing position, the splicing assembly is located at the opposite side of the expiring Web run in a position relative to the latter ensuring the proper action of its rollers 96 and 97 and its knives 108 on the expiring web run upon the tripping or release of the associated latches 98 and 111.

In the illustrated rollstand, the movement of splicing assembly 48 toward the expiring web run is limited by a stop 145 (FIGS. 1 and 2) engageable by an abutment 146 on the lower end of actuating arm 132, and the position of stop 145 is changed in accordance with the displacement of the expiring web run as the new web roll approaches splicing position. The position of stop 145 is changed in accordance with the displacement of the expiring web run by mounting stop 145 at the end of an arm 147 which is secured on the inner end of shaft 80 so as to be angularly displaced with bracket 79 carrying sensing device 49 when cam follower roller 86 of that bracket is engaged by one or the other of the contoured portions of cam 87 It will be apparent that the angular position of arm 147 on shaft 80 and the contour of cam 87 are selected so' to the expiring web run. Contact 60d is interposed between a lead 148 extending from line L and a lead 149 extending to a time delay relay 150 which is connected to ground, as at 151. Contact 60e is interposed between a lead 152 extending from line L and a lead 153 extending to a normally closed contact 165a of a hereinafter referred to cam actuated switch 165, and contact 165a is, in turn, connected by a lead 154 to the coil of relay 60 so as to constitute a hold circuit for relay 60. Relay 150 has a normally open contact 150a interposed between a lead 155 extending from line L and a lead 156 extending to panel 68.

It will be apparent that, when relay 60 is tripped or actuated, contact 60d is closed to energize time delay relay 150 and contact 60a is closed to complete the hold circuit for relay 60 through the normally closed contact 165a.

Thus, relay 60 is maintained in its tripped or actuated condition by continued energization thereof through lead 152, contact 60a, lead 153, contact 165a and leads 154 and 74 until contact 165:: is opened, as hereinafter described.

The time delay provided by relay 150 between the movement of its energization and the tripping or actuation of the relay for closing of its contact 150a is sufiicient to permit the drive 42 to be moved to its operative position for acceleration of the new web roll at splicing position up to a peripheral speed equal to the speed of the expiring web run.

As indicated previously, at the moment when relay 60 is tripped or actuated to deenergized motor 16 with the new web roll at splicing position, sensing device 49 is disposed to direct its light beam against the adjacent end surface of the new web roll at a predetermined distance radially inward from the periphery of the roll. Further, each new web roll has a reflective mark M (FIGS. 1 and applied to the end surface thereof at the same predetermined distance radially inward from the periphery of the roll, and at a predetermined angular position relative to the leading edge of the web of the new roll.

So long as relay 60 remains energized through its above described hold circuit, contact 601: is open to deenergize control anel 68, whereby sensing device 49 is inoperative to sense or detect rnark M during the acceleration of the new web roll by drive 42. However, when time delay relay 150 is tripped or actuated, at which time the peripheral speed of the new web roll equals the speed of the expiring web run, the closing of contact 150:! again energizes control panel 68 by way of lead 155, contact 150a and lead 156. Upon such reenergization of control panel 68, sensing device 49 directs its light beam against the adjacent end surface of the new web roll at the location of the circular path traveled by reflective mark M. When the rotated new web roll attains a predetermined angular position about its own axis, mark M reflects the light beam into the photocell of sensing device 49 and control panel 68 responds to such actuation of the photocell by directing an electrical signal or current through a lead 157 to energize a solenoid valve 158 (FIG. 5). When thus energized, solenoid valve 158 supplies fluid under pressure to cylinder 127 which thereby causes disengagement of latches 98, as previously described.

' Thus, rollers 96 and 97 press the expiring web run against the periphery of the new web roll at the predetermined position on the periphery where adhesive has been applied, thereby to splice the expiring web run to the periphery of the new roll. During the next revolution of the new web roll, sensing device 49 again detects mark M and panel 68 responds thereto by directing an electrical signal or current through a lead 159 to energize a solenoid valve 160. When thus energized, valve 160 supplies fluid under pressure to cylinder 128 which thereby causes release of latches 111, as previously described. Thus, knives 108 are projected to cut the expiring web run at a predetermined distance from the splice.

It will be noted that, although relay 158 remains energized and in its tripped condition so as to energize panel 68 by way of contact 1500 until the hold circuit for relay 60 is broken, as hereinafter described, control panel 68 may be arranged to energize solenoid valves 158 and only in response to the detection by sensing device 49 of mark M during the first two revolutions of the new web roll following the tripping of relay 159.

After the expiring web run has been spliced to the new web roll and the expiring web run has' been cut, as described above, the new web roll is moved to the normal running position R and the expired roll is moved to the loading position, at which it is removed and replaced by the next new web roll. As shown on FIG. 5, if desired, the movement of the new web roll to normal running position R may be manually initiated by an operator controlled push-button switch 161 having a normally open contact 161a between a lead 162 extending from line L and a lead 163 extending to motor starter 64 by way of lead 63, Switch 161 may be depressed to continue the operation of motor 16 until one or the other of two cams 164 (shown in broken lines on FIG. 1) mounted for turning with spider arms 13a and 13b engages and opens a normally closed contact 1651; of the cam actuated switch 165 interposed in lead 163 to halt the spider arms with the ends thereof at the normal running and loading positions, respectively.

As shown on FIG. 5, push-button switch 161 further has a normally closed contact 161!) interposed in the hold circuit 144 of relay 139, and such contact 161b is opened when switch 161 is depressed. Opening of contact 161b deenergizes relay 139 which, in turn, deenergizes valve 138 so that fluid under pressure is thereby supplied to cylinder 134 through conduit 136. Thus, during movement of the new web roll to normal running position, cylinder 134 acts to move splicing assembly 48 to its inoperative position.

It will be noted that the engagement of one or the other of cams 164 with switch 165 also opens the contact 165a thereof so as to interrupt the hold circuit of relay 60 when the new web roll reaches the normal running position. The return of relay 60 to its deenergized condition closes contacts 60a, 60b and 600 and opens contacts 68d and 602. Opening of contact 60d deenergizes relay 150 so as to open its contact 150a and thereby deenergize panel 68. The closing of contact 60a causes reenergization of panel 53, but the presence of the new web roll at normal running position R intercepts the light beam 51 from sensing device 50.

It will be apparent that, in the above described embodiment of the invention, a single photocell of the sensing device 49 is employed for detecting the periphery of a new web roll approaching splicing position, thereby to ensure that the new web roll and splicing assembly 48 are in predetermined locations relative to the expiring web run when splicing is effected, and also for detecting a predetermined angular position of the new web roll about its own axis so that the actuation of splicing rollers 96 and 97 and of knives 108 can be timed in relation to such angular position.

However, as shown on FIG. 6, the previously described sensing device 49 mounted for movement in accordance with the displacement of the expiring web run as the new web roll approaches splicing position may be replaced by a sensing device 49' which is similarly movable, but includes two photoheads 166 and 167 each having a light source and a photocell. The photoheads 166 and 167 are spaced apart, as shown, so that, when photohead 166 is isposed to detect the periphery of a new web roll Ib at the desired splicing position thereof in relation to the expiring web run, the other photohead 167 is disposed to track the circular path traveled by the reflective mark M on the adjacent end surface of the new roll when the latter is rotated at splicing position.

Although the arrangement of FIG. 6 requires two photoheads in place of the single photohead employed in the first described embodiment, it makes possible a considerable simplification of the electrical circuits by reason of the fact that energization of motor 16 can be effected at the instant when photohead 166 detects the periphery of the new web roll.

As shown on FIG. 7, the electrical circuits for use with sensing device 49' are generally similar to those described above with reference to FIG. 5, but with the following omissions and changes:

Relay 60 is a simple relay, as distinguished from the time delay relay 60, and omits the normally closed contact 60b of the latter. Relay 72 of FIG. is eliminated, and relay 60 is energized directly from control panel 68' by way of the lead 70'.

Although FIG. 7 does not show the relay 139, the solenoid valve 138 and the switch 161 of FIG. 5, it is to be understood that such components and the corresponding connections are also to be included in the modified circuits.

The operation of the circuits shown on FIG. 7 are believed to be apparent therefrom. However, specific note may be taken of the fact that, when sensing device 50 detects the reduction of the diameter of the expiring web roll Ia to the predetermined dimension and control panel 53 sends the corresponding signal through lead 56, contact 60a and lead 59 to energize relay 58, the closing of contact 58a serves to energize the motor 16 through closed contact 60'c and also to energize only the photohead 166 of sensing device 49'. When photohead 166 detects the periphery of the new web roll at the predetermined splicing position relative to the expiring web run, control panel 68' sends a signal through lead 70 to energize relay 60 and thereby immediately trip or actuate the same. Thus, motor 16 is immediately deenergized and relay 60' is held in energized condition by way of the hold circuit 152, 60 'e, 153, 165a and 154. So long as relay 60 is energized, the open contact 6021 deenergizes relay 58 and also renders sensing device 50 inoperative. The open contact 58a of deener gized relay 58 causes deenergization of photohead 166.

Energizing of relay 60 further causes energization of time delay relay 150 which is tripped or actuated after the new web roll at splicing position has been accelerated to the desired speed. When relay 150 trips, the closing of its contact 150a completes the circuit for energizing the photohead 167 which thereafter detects the angular position of the rotated new web roll by responding to reflective mark M, and causes panel 68 to emit control signals for successively energizing the roller trip valve 158 and the knife trip valve 160 by way of leads 157 and 159. At the conclusion of the splicing operation, the splicing assembly is returned to its inoperative position and the new web roll is moved to the normal running position in the manner described above with reference to FIG. 5.

Although illustrative embodiments of this invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention which is intended to be defined by the appended claims.

What is claimed is:

1. In a rollstand for deliverying a web continuously from one web supply roll after another, the combination of support means for carrying a first web roll from which a web is being unwound and a second web roll which is to have its periphery spliced to the web from the first roll, said support means being displaceable to move said second roll toward splicing position and to move said first roll simultaneously in an opposite direction,

means for guiding a run of the web extending from said first roll across the path of movement of said second roll toward splicing position, said run being displaced toward said second roll by a displacement of said support means to move said rolls as aforesaid,

sensing means to detect the approach of the periphery of said second roll to splicing position, and means for changing the position of said sensing means in accordance with the displacement of said run as said second roll and said run approach each other, whereby said sensing means detects said second roll at a predetermined location thereof relative to said run irrespective of the diameter of said second roll.

2. A rollstand according to claim 1; wherein said means for changing the position of said sensing means includes cam means displaceable with said support means, and movable mounting means carrying said sensing means and having follower means engaging said cam means so that said changing of the position of the sensing means is determined by said cam means in response to displacement of the latter with said support means.

3. In a rollstand for delivering a web continuously from one web supply roll after another, the combination of support means for carrying a first web roll from which a web is being unwound and a second web roll which is to have its periphery spliced to the web from the first roll, said support means being displaceable to move said second roll toward splicing position and to move said first roll simultaneously in an opposite direction,

means for guiding a run of the web extending from said first roll across the path of movement of said second roll toward splicing position, said run being displaced toward said second roll by a displacement of said support means to move said rolls as aforesaid,

sensing means to detect the approach of the periphery of said second roll to splicing position,

splicing means positionable to act on said run when said second roll is at splicing position, and

means for changing the respective positions of said sensing means and said splicing means in accordance with the displacement of said run as said second roll and said run approach each other, whereby said sensing means detects said second roll, and said splicing means is positioned, at predetermined respective locations thereof relative to said run irrespective of the diameter of said second roll.

4. In a rollstand for delivering a web continuously from one web supply roll after another, the combination of support means for carrying a first web roll from which a web is being unwound and a second web roll which is to have its periphery spliced to the web from the first roll, said support means being displaceable to move said second roll toward splicing position and to move said first roll simultaneously in an opposite direction, means for guiding a run of the Web extending from said first roll across the path of movement of said second roll toward splicing position, said run being displaced toward said second roll by a displacement of said support means to move said rolls as aforesaid,

sensing means to detect the approach of the periphery of said second roll to a splicing position, and

splicing means urged to move toward said run so as to be operable thereon,

stop means for limiting movement of said splicing means toward said run, and

means for changing the respective positions of said sensing means and said stop means in accordance with the displacement of said run as said second roll and said run approach each other, whereby said sensing means detects said second roll, and said stop means limits movement of said splicing means, at

predetermined respective locations thereof relative to said run irrespective of the diameter of said second roll.

5. A rollstand according to claim 4; wherein said means for changing the positions of said sensing means and stop means includes cam means displaceable with said support means, and movable mounting means carrying said sensing means and stop means and having follower means engaging said cam means so that said changing of the positions of said sensing means and stop means is determined by said cam means in response to displacement of the latter with said support means.

6. In a rollstand for delivering a web continuously from one web supply roll after another, the combination of support means for carrying a first web roll from which a web is being unwound and a second web roll which is to have its periphery spliced to the web from the first roll, said support means being displaceable to move said second roll toward splicing position and to move said first, roll simultaneously in an opposite direction,

means for guiding a run of the web extending from said first roll across the path of movement of said second roll toward splicing position, said run being displaced toward said second roll by a displacement of said support means to move said rolls as aforesaid,

drive means energizable to displace said support means,

sensing means to detect the approach of the periphery of said second roll to a splicing position,

means to deenergize said drive means in response to detection of said second roll by said sensing means, and

means for changing the position of said sensing means in accordance with the displacement of said run as said second roll and said run approach each other, whereby said sensing means detects said second roll at a predetermined location thereof relative to said run to provide a uniform splicing position of said second roll relative to said run irrespective of the diameter of said second roll.

7. A rollstand according to claim 6; further comprising splicing means urged to move toward said run so as to be operable thereon, and

stop means for limiting movement of said splicing means toward said run; and wherein said means for changing the position of the sensing means also changes the position of said stop means in accordance with the displacement of said run as said second roll and said run approach each other, whereby said stop means limits movement of said splicing means at a predetermined location relative to said run irrespective of the diameter of said second roll.

8. A rollstand according to claim 7; wherein said sensing means also detects a predetermined angular position of said second roll about its axis when said second roll is at splicing position; and

further comprising means responsive to the detection of said predetermined angular position of the second roll by said sensing means to cause operation of said splicing means.

9. A rollstand according to claim 8;

wherein said sensing means is disposed by said means for changing its position so that, when the sensing means detects the periphery of said second roll at said predetermined location, the periphery of said second roll is spaced a predetermined distance from said run; and

wherein said means to deenergize the drive means includes time delay means providing a predetermined time interval between the detection of the periphery of said second roll by said sensing means and deenergizing of said drive means, during which time 10. A rollstand according to claim 8; wherein said sensing means includes first and second sensing elements both movable by said means for changing the position of the sensing means and being positioned relative to each other so that, when said first sensing element responds to the periphery of said second roll at said predetermined location relative to said run, said second sensing element responds to said predetermined angular position of the second roll.

11. In a rollstand for delivering a web continuously from one web supply roll after another, the combination of a support means for carrying a first web roll from which a web is being unwound and a second web roll which is to have its periphery spliced to the web from the first roll, said support means being displaceable to move said second roll toward splicing position and to move said first roll simultaneously in an opposite direction,

means for guiding a run of the web extending from said first roll across the path of movement of said second roll toward splicing position, said run being displaced toward said second roll by a displacement of said support means to move said rolls as aforesaid,

sensing means to detect the approach of the periphery of said second roll to splicing position,

movable mounting means carrying said sensing means for movement thereof toward and away from said run at the side of said run facing the second roll moving toward splicing position, and

positioning means responsive to a displacement of said support means to initially displace said mounting means in the direction moving said sensing means toward said run and thereafter displacing said mounting means in the opposite direction so as to move sensing means in accordance with the displacement of said run as said second roll and said run approach each other, whereby said sensing means detects said second roll at a predetermined location thereof relative to said run irrespective of the diameter of said second roll.

12. A rollstand according to claim 11; wherein said positioning means includes cam means displaceable with said support means, and cam follower means engaging said cam means and coacting with said mounting means for the sensing means.

13. A rollstand according to claim 11; wherein said support means is displaceable by turning about an axis located between said first and second rolls, and said mounting means is displaceable =by rocking about an axis parallel to the turning axis of said support means; and wherein said positioning means includes a cam rotatably coupled with said support means so as to turn therewith, said cam having a cam track with at least one contoured portion, and cam follower means engaging said cam track and coacting with said mounting means so as to rock the latter during engagement of said contoured portion of the cam track with said follower means.

14. A rollstand according to claim 11; further comprising splicing means urged to move toward said run so as to be operable thereon,

stop means for limiting movement of said splicing means toward said run, and

means connecting said stop means with said mounting means for displacement with the latter about said rocking axis, whereby said stop means is moved with said sensing means in accordance with the displacement of said run as said second roll and said run approach each other so as to limit movement of said splicing means at a predetermined location relative to said run irrespective of the diameter of said second roll.

15. A rollstand according to claim 14; wherein said sensing means also detects a predetermined angular position of said second roll about its axis when said second roll is at splicing position; and further comprising means responsive to the detection of said predetermined angular position of the second roll by said sensing means to cause operation of said splicing means.

16. A rollstand according to claim 15; further comprising drive means energizable to displace said support means, and means controlled by said sensing means to deenergize said drive means in response to detection of said second roll by said sensing means.

17. A rollstand according to claim 16; wherein said sensing means is disposed by said positioning means to detect the periphery of said second roll when said periphery and said run are spaced apart by a predetermined distance; and wherein said means .to deenergize the drive mined angular position of said second roll at splicing posi- 1 tion.

18. A rollstand according to claim 16; wherein said sensing means includes first and second sensing elements positioned relative to each other to respectively detect the periphery of said second roll at splicing position and said predetermined angular position of the second roll when at splicing position.

References Cited UNITED STATES PATENTS 2,621,865 12/1952. Wieking 242-583 2,963,235 12/ 1960 Pedersen et al. 24258.3

FMNK I. COHEN, Primary Examiner.

LEONARD D. CHRISTIAN, Assistant Examiner. 

1. IN A ROLLSTAND FOR DELIVERYING A WEB CONTINUOUSLY FROM ONE WEB SUPPLY ROLL AFTER ANOTHER, THE COMBINATION OF SUPPORT MEANS FOR CARRYING A FIRST WEB ROLL FROM WHICH A WEB IS BEING UNWOUND AND A SECOND WEB ROLL WHICH IS TO HAVE ITS PERIPHERY SPLICED TO THE WEB FROM THE FIRST ROLL, SAID SUPPORT MEANS BEIN DISPLACEABLE TO MOVE SAID SECOND ROLL TOWARD SPLICING POSITION AND TO MOVE SAID FIRST ROLL SIMULTANEOUSLY IN AN OPPOSITE DIRECTION, MEANS FOR GUIDING A RUN OF THE WEB EXTENDING FROM SAID FIRST ROLL ACROSS THE PATH OF MOVEMENT OF SAID SECOND ROLL TOWARD SPLICING POSITION, SAID RUN BEING DISPLACED TOWARD SAID SECOND ROLL BY A DISPLACEMENT OF SAID SUPPORT MEANS TO MOVE SAID ROLLS AS AFORESAID, SENSING MEANS TO DETECT THE APPROACH OF THE PERIPHERY OF SAID SECOND ROLL TO SPLICING POSITION, AND 